Track bumper



v G. lsoNo 1,745,014

TRACK BUMPER 3 Sheets-Sheet l Filed Deo. 11, 1928 li "mi Jan. 2s, 1930. @mme 1,745,014

TRACK BMRER Fledpec. 11, 192e s sheets-smet 2 Lm/Lr IMM,

l VG. ISONO Jan. 28, 1930.

TRACK BUMPER' Filed Dec. 1l, 1928 3 Sheets-Sheet 3 uw MMM a bww f 5%/ Patented Jan. 28, 1930 UNITED 4sieri-1S ,PATENT OFFICE `(Sl-'UNJ'Ik ISONO, 0F HAIMLADEIRA-CHO, SEHOKU-GUN, OSAKA, JAPAN TRACK BUMPER Application led December 11,1928,V Serial No.1325,207, and inJ'apan January 7, 1928.

This invention relates to track bumpers to be provided at the dead endof a railway track.

One of the objects of the invention is to provide a track bumper which will stop an oncoming car or a train of cars, not in an instantaneous manner, Vbut after a short brakingrdistance, thus avoiding any serious injuries either to the cars or to the bumper itself. n l f Y Another object of the invention isto so design the bumperl as to cause the brake shoes to press uniformly against the rails when the bumper is actedupon.

With these objects in view, the invention consists of an impact block, a pair of. front brakeV shoes contacting with the track rails, or with rails specially provided for that purpose, at the bottom face of the top'fiange or tread of the rails and also at the web thereof, and a pair ofy rear brake shoes com tacting with the rails at the top face of the tread, front and rear leg members` connecting the respective shoes with the impact block, a resilient means to press the front brake shoes laterally against the rails and a cam means, such as, forexample, anin'-l clined shoulder providedon one set'or pair of shoes anda pin or the like vserving as a roller operating between the two'sets in such a manner ythat one set can be displaced longitudinally with respect to the other with a minimum friction, so that both sets kof shoes are brought: closer togetherr when the bumper device is acted upon.

` When a'car collides with the trackbumper, y

a pull exerted Aon the front leg-members, a push exertedon the, rear leg members and. the corresponding forcespex'erted'on the re-' spective shoes'as produced "by the operation of cam means, in (3o-operation with Ithe "forces exerted bythe resilient meansycause thel shoes to uniformly lpress upon, the rails, creating sufficient frictio'nvto stop run-away cars within a'certainy shortV andjpre-determined distancef l.'

Referring to the accompanying drawings.

Figurelpis'aside view of a bumper device according to r'myf invention.

Figure 3 is a fragmental side view, on an enlarged scale, of the rear portion of thev device.` y Figure 4 is a horizontal section on line l--llofFignSfA i Figure 5 is a vertical of Figure 3.. Figurep is a of Figure 3. n

yigure? is a fragmentalside viewfof the front portion of thedevice. 1 Figure 8is a horizontal section on line 8 8 of Figure 7.`v l Q l', Figure 9 is a vertical sectionon line 9 9 of Figure 7. A e f Figure 10 is a side view ofthe lower portion of theJ front legmember ofthe device. Figurell is a bottom end view thereof. Figure k12 is a detail ,sidey View of they device, partly. Lbroken away, showing rear cam means operating between the front and the rear brake shoes. Figure 13.*is 'a section' on line 13 13 of Figure 12 vlooking in the direction ofthe arrows. y j f* Figure 14k is avertical. section on line 1,4 147of Figure 12.y Figure 15 is acentral section, 'on an enlarged scale, of the device, with the leg mem-v bers removed, showing in detail spring means to exert a lateral pressure on the front section on line 5 5 vertical sectionl on line 6 6 brake: shoes. l Figure'l isk a 4horizontal section on line 16 16 ofFigure 15". l -fFigure`-17is a jvertical section Online 117 17-' of Figure 1 5.A

Figure 18 is avertical section on line 1,8 18-ofy Figure 15, showingA theV distance piece disposed between theinner front shoes. Referringpnow more particularly tothe accompanyingv drawings, 1,y 1 are the track rails; Between these ,railsiand constituting the "stationary part of the `device are two auxiliary lrails 2, l2l of I-section. mounted on each of 'the auxiliary rails are pairs of front brakeshoes 3, 3 and rear brake shoes 4, 4. `Fivotally'and loosely connected, as by pin 5`and elongatedaperture 6,'tothe front Shoes and atthe frontend thereof, is

` a pair of frcntileg-'mernberaf 'fastened torear leg members and the impact block are secured together by a pin at the apex-ofthe triangle',

The front brakeshoes 3 are substantially of L-section, eachconsisting of a. horizontal flange portion ,or foot 14 and a vertical web port1on`15 (Fig. 15); the flange portion .14 contacting at its Itip endwith theweb vofthe auxiliary or brake rail 2, and atitsupper face with theunder sideof thetop flange or tread of the rail;

VThe .rear brake shoe-4 is disposed' interinediately of`a pair of front brake shoes- 3 andzlatly.` presses upon ,the yupper surface. of

the top ange orA tread ofthe auxiliary rail.

The rear; portions of` the front, shoes-and the front portions of the rear shoeslie in juxtaposition, .the latter: being interposed lbetween the' former. The front and thefrear shoes are formed with elongated, backwardly and downwardly; sloping apertures 16', 161

and]17.17"to.1egistelr eachother, through whichsextend pins or rollers18, 19 respectively. Breferablyjthe front shoes maybe provided. with inwardly projecting flanges 20, 21 at these points, withsloping Ishoulders 22, 23 borderingon the respective apertures. When theA 'rear shoes are pushed backwardly rela-tively to the front shoes, as hereinafter more fully described, :the pins 18 and19 rolling along 'the inclined edges ofthe .apertures serve toV guide. therelative motion with a minimum of friction.

Disposedat the front portion of the front shoes` and, mounted on the pin5 is a transmission bar 24 abutting at its freeend against theiforewardend of therear shoe.

At the middle portion-of, the. device-there isa pair, ofleif'ers25, 25, substantially of channely section, which press inwardly the unit or assemblage consisting of two pairs of front shoes, auxiliary brakeirails` interposed therebetween, anda distance piece-26, all held, together by meansof a bolt. 27. and a nut. 28, l"lhe apertures. formed intherear, for, theibolt 27, toextiendgthrough are elongated, as .at 429, (Fig, 11) zto xallow a. longitudinal; movement olthereary shoes. relativeV to the-front, shoes. Betweenthe upper ends of.'the,lev,ers 25, there; are interposedL comesson sprngs..3031,armnged in a Casingl 32,;whioh ismounted on. a` guide shaftj. These springs exert an, outward pressure. in al opposite directions.againstthelevers, asinsaid free ends,4 Thefront vleg members, the.

dicated by the arrows 34, thus forcing the right-hand lever to move towards the ri ht, and the left-hand lever toward the eft through the intermediary of a sleeve 35 slidably mounted on the guide shaft. These outward pressures are transmitted to the group of shoes as inwardly-directed compressive forces, ashown by thearrows 36owing to the presence of the head of the bolt 27 andthe nut 28. The auxiliary rails 2 are somewhatiloosely mounted uponit-he sleepers, so that they can move slightly in lateral directions, and in this way, the compression is transmitted to the elementslyingVA between the two levers.

Tgheabove mentioned sprin meanspro vides a friction of a suitab ,e magnitude against the sliding motion of the front brake shoes ltobring about .the effective operation of cam meansincluding the rollers 18,` 19 indueinga proper grippmg orA bitingv action ofthe shoesron the -brakerails 2. Besides,lit ser,v.esto.uniformly distribute the upward pressure of the front shoes 3 acting against the'lower surfaces of the treads of the brake rails, owing, to the pressure exerted on the lowermost edges ofthe flanges or. feet. 1410i said shoes.v

The operationis as follows Then a ,car coll-ides with; the impact block 1,2` of the track.A bumper in the directionfindicated by the arrow 37, in Fig. 1, the force. of collisionwillbe divided into a pullonthe front-leg members] andapush on themrear leg memberslO. The pull onthe front leg members may again be decomposed into a verticallyr-andf upwardly-directed compof nent andv a. horizontallyffand, rearwardly-.- directed component. The former tends tolift the front. shoes, thereby, pressing theirfeet Magainst `the underside of. the treads of the auxiliary rails, and thusy serves to` increase thesurface friction.

'Il hepush onthe rear leg members may also be decomposed into a,verticallyand downwardly-fdirected component and, a horizonta1ly.-.and rearward1y-.directed` component. The vertical component acts topress the rear shoes4 uponthe top surfaceof the auxiliary rails and increases theA friction, while the horizontal component, in co-operation with the horizontal.y component as transmitted throughfthe intermediary of the transmission bar 2,4, drives therearshoes `4 rearward relatively to thefrontvshoes as made possible by the,elongation/of theapertures pertaining to they. pins or rollers 18,19. In this relative movement of. the rear shoes with res ect to thefront shoesas,g u ided by therolersl, 19extending, through the respectivej inclined` apertures formed in the brakeshpes, tiheishoes are .brought `vertically closer to ether .against the,r.ailsa nd the friction is furteriincreased. The slope of the apertures should be sopro-A portionedain, relation to the inclination ofthe leg members that the resulting vertical pressures on the rails are uniform along the lengths of the shoes.

The device, as a whole, is `driven back a certain distance by the force of the collision, un-

til the kinetic energy of the colliding body hasfbeen expended by the initial side friction due to the springs and the increased friction between the brake shoes and the auxiliary lo brakerails.

After the device has thus been operated, the compression springs 30, 31 are loosened by unscrewing the nut on the guide shaft 33, the device is brought back to its initial position and the springs again restored to their normal compressed state, to'be ready for another emergency. e

What I claim is:

1. A track bumper comprising an impact block, a shoe contacting upwardly with a rail, another shoe contacting downwardly with the rail, and two leg members pivotally connecting the respective shoes with the said impact block, means to press one of the shoes upon the rail to exert an initial friction thereon, the said shoes beingdisplaceable with respect to each other, and cam means on the shoes to bring them closer together when a force of collision tends to separate them in longitudinal direction.

2. A track bumpercomprising an impact block, a shoe contacting upwardly with a rail and pressed to the rail from a side thereT of, another shoe contacting downwardly with the rail, said shoes having inclined aperturesv formed therein, two leg members pivotally connecting the respective shoes with the said impact block, a roller extending through the inclined apertures in the shoes, and means to q Vpress one of the shoes laterally against the rail.

8. A track bumper comprising an impact block, a shoe contacting upwardly with a rail and pressed to the rail from a side thereof,

5 another shoe contacting downwardly with the rail, said shoes being formed with registering inclined apertures, two leg members of substantially equal lengthspivotally connecting the outer ends of the respective shoes with the said impact block, a roller extending through the said apertures, and spring means to normally press the first-mentioned shoe` against the rail.

In testimony whereof I ax my signature.

GUNJI ISONO. 

